关于神经病学PBL教学中心理因素的思考

神经病学是涉及多个基础学科的临床专门学科,其内容复杂抽象,令学生望而生畏。PBL是学生自主学习建构知识和教师引导的教学模式,有利于学生克服畏难情绪,提高学习效率。根据我们的实践体会,教师与学生的心理是影响PBL教学效果的重要因素。只有把握好教学过程中的心理因素,才能使PBL的优势真正得以体现。     

Wistar大鼠幼年期丰富环境刺激对其社会竞争行为的影响

目的：探讨大鼠幼年期丰富环境经历对其成年后焦虑样行为和社会竞争行为的影响。方法：幼年期Wistar大鼠（生后21天）分为标准饲养组（对照组）和丰富环境刺激（EE）组。对照组为持续在标准实验室饲养条件下饲养;丰富环境组为生后21天至行为学检查时持续在丰富环境下饲养。在生后70天进行行为学检测：采用高架十字迷宫方法测试焦虑样行为;采用社会优势管道试验观察社会竞争性行为。结果：高架十字迷宫实验结果显示,与对照组相比,丰富环境组在开放臂的时间和次数显著增加;优势管道实验结果显示丰富环境刺激组大鼠的社会竞争力明显下降。结论：大鼠幼年期丰富环境刺激可改善大鼠的焦虑样情绪,但导致大鼠社会竞争力下降。     

液质连用分析重组胰高血糖素样肽-1受体激动剂肽图

目的：建立高效液相系统肽图分析法,用于重组胰高血糖素样肽-1受体激动剂（rExendin-4）的质量控制。方法：应用高效液相系统摸索最佳胰蛋白酶切和色谱条件,并采用液质联用系统分析肽段的精确相对分子量和氨基酸序列。结果：根据酶切条件摸索,确定酶切条件为：rExendin-4原液与胰蛋白酶按照质量比为100：1混匀,37℃酶切4小时,根据肽段的色谱保留时间、相对分子质量及对其碰撞诱导解离质谱的解析结果,归属出肽图中各肽段所在的色谱峰,与理论值完全一致。结论：本法精确度高、重复性好、自动化程度高,能够用于rExendin-4原液肽图分析。     

不同粘度对比剂对冠状动脉造影患者肾功能的影响

目的：对比剂肾病（CIN）是介入治疗中常见并发症之一。由于对比剂肾病发病机制复杂,其确切的机制尚不明确,有研究认为应用渗透压相似的对比剂,高粘度组对比剂引起CIN的几率明显高于低粘度组。本研究探讨接受不同粘度对比剂冠状动脉造影检查的患者术后引起肾功能损害的差异及其可能的机制。方法：80例接受冠状动脉造影检查的患者随机分为两组。分别为20℃碘海醇组、37℃碘海醇组,每组各40例。分别于冠脉造影前8h、冠脉造影后48h采集同一患者肘正中静脉血进行血清肌酐（Scr）、血清胱抑素C（CysC）检测,并对数据进行统计学分析。结果：两组患者组间比较基本资料无明显差异,两组患者术后Ser、CysC较术前均升高,差异均有统计学意义（P〈0．05）;20℃碘海醇组术后Scr较37℃碘海醇组升高不明显,差异无统计学意义（P〉0．05）;20℃碘海醇组术后CysC较37℃碘海醇组升高明显,差异有统计学意义（P〈0．05）。结论：冠脉造影检查时．对比剂对患者的肾功能有损害;选择低粘度对比剂可能减少其对冠状动脉造影患者的肾功能的不良影响;其作用机制可能与对比剂改变血液粘滞性,从而影响肾血流有关。     

Toll‐like receptor 9 protects non‐immune cells from stress by modulating mitochondrial ATP synthesis through the inhibition of SERCA2

Toll‐like receptor 9 (TLR9) has a key role in the recognition of pathogen DNA in the context of infection and cellular DNA that is released from damaged cells. Pro‐inflammatory TLR9 signalling pathways in immune cells have been well investigated, but we have recently discovered an alternative pathway in which TLR9 temporarily reduces energy substrates to induce cellular protection from stress in cardiomyocytes and neurons. However, the mechanism by which TLR9 stimulation reduces energy substrates remained unknown. Here, we identify the calcium‐transporting ATPase, SERCA2 (also known as Atp2a2), as a key molecule for the alternative TLR9 signalling pathway. TLR9 stimulation reduces SERCA2 activity, modulating Ca²⁺ handling between the SR/ER and mitochondria, which leads to a decrease in mitochondrial ATP levels and the activation of cellular protective machinery. These findings reveal how distinct innate responses can be elicited in immune and non‐immune cells—including cardiomyocytes—using the same ligand‐receptor system.     

C-type lectin-like molecule-1 (CLL1)-targeted TRAIL augments the tumoricidal activity of granulocytes and potentiates therapeutic antibody-dependent cell-mediated cytotoxicity

The therapeutic effect of anti-cancer monoclonal antibodies stems from their capacity to opsonize targeted cancer cells with subsequent phagocytic removal, induction of antibody-dependent cell-mediated cytotoxicity (ADCC) or induction of complement-mediated cytotoxicity (CDC). The major immune effector cells involved in these processes are natural killer (NK) cells and granulocytes. The latter and most prevalent blood cell population contributes to phagocytosis, but is not effective in inducing ADCC. Here, we report that targeted delivery of the tumoricidal protein tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to granulocyte marker C-type lectin-like molecule-1 (CLL1), using fusion protein CLL1:TRAIL, equips granulocytes with high levels of TRAIL. Upon CLL1-selective binding of this fusion protein, granulocytes acquire additional TRAIL-mediated cytotoxic activity that, importantly, potentiates antibody-mediated cytotoxicity of clinically used therapeutic antibodies (e.g., rituximab, cetuximab). Thus, CLL1:TRAIL could be used as an adjuvant to optimize the clinical potential of anticancer antibody therapy by augmenting tumoricidal activity of granulocytes.     

Plant Virus Particles Carrying Tumour Antigen Activate TLR7 and Induce High Levels of Protective Antibody

Induction of potent antibody is the goal of many vaccines targeted against infections or cancer. Modern vaccine designs that use virus-like particles (VLP) have shown efficacy for prophylactic vaccination against virus-associated cancer in the clinic. Here we used plant viral particles (PVP), which are structurally analogous to VLP, coupled to a weak idiotypic (Id) tumour antigen, as a conjugate vaccine to induce antibody against a murine B-cell malignancy. The Id-PVP vaccine incorporates a natural adjuvant, the viral ssRNA, which acts via TLR7. It induced potent protective anti-Id antibody responses in an in vivo mouse model, superior to the “gold standard” Id vaccine, with prevalence of the IgG2a isotype. Combination with alum further increased antibody levels and maintained the IgG2a bias. Engagement of TLR7 in vivo was followed by secretion of IFN-α by plasmacytoid dendritic cells and by activation of splenic CD11c^hi conventional dendritic cells. The latter was apparent from up-regulation of co-stimulatory molecules and from secretion of a wide range of inflammatory cytokines and chemokines including the Th1-governing cytokine IL-12, in keeping with the IgG2a antibody isotype distribution. PVP conjugates are a novel cancer vaccine design, offering an attractive molecular form, similar to VLP, and providing T-cell help. In contrast to VLP, they also incorporate a safe “in-built” ssRNA adjuvant.     

非酒精性脂肪肝病大鼠肝脏SOCS-3的表达与吡格列酮干预研究

目的：探讨SOCS-3在非酒精性脂肪肝病（NAFLD）发病中的作用以及吡格列酮的干预作用。方法：29只雄性SD大鼠随机分为正常对照组（8只）,高脂饮食组（21只）。饲养8周后,从高质饮食组随机抽取5只大鼠证实造模成功后,将该组余下的16只大鼠继续以高脂饲料喂养,并随机分为NAFLD对照组（8只）;吡格酮干预组（8只）,予以吡格列酮3mg·kg^-1·d^-1灌胃。16周末,处死所有大鼠,检测血糖、血胰岛素、血脂、肝脏SOCS-3mRNA和SREBP-lcmRNA表达及肝脏病理学。结果：与正常对照组相比,NAFLD组血糖、血胰岛素、血脂、肝脏脂肪变水平及肝组织SOCS-3mRNA、SREBPlCmRNA表达显著上调。吡格列酮干预组sOCS．3mRNA、SREBP-1cmRNA表达较NAFLD组下调,且血糖、血胰岛素、血脂、肝脏脂肪变水平下降。SOCS-3mRNA表达水平与胰岛素抵抗指数、SREBP．1cmRNA表达水平、肝脂肪变成显著正相关。结论：SOCS-3可能通过胰岛素抵抗及上调肝组织SREBP-lcmRNA表达参与NAFLD发病,吡格列酮能抑制肝脏SOCS-3的表达,对NAFLD有一定治疗作用。     

妊娠对于父源性皮肤移植存活时间的影响

母胎耐受机制的阐明,将为器官移植免疫耐受方案的研究提供重要启示.本研究旨在阐明妊娠状态对父系来源移植皮片的存活是否有保护作用.2月龄雌性C57BL/6小鼠和2～4月龄BALB/c雄性小鼠同笼受孕.采用流式细胞技术确定妊娠过程中调节性T细胞（Treg）比例的时间变化规律.以单向混合淋巴细胞反应（MLR）手段比较研究妊娠对于父系来源脾细胞刺激后产生的增殖反应的影响.通过同种异体小鼠全厚皮片移植模型,观察妊娠对于父系来源移植皮片的存活是否具有保护作用.并用分子生物学技术研究此种效能的可能机制.结果显示,C57BL/6小鼠妊娠过程中,Treg占CD4＋T细胞的比例从妊娠前的4.2%逐渐上升,受孕8天左右达到高峰值（6.8%）,此后开始下降并逐渐回复至基线水平.MLR结果表明,针对父系来源脾细胞的刺激,妊娠组较对照组呈现显著的低反应性,其平均刺激指数分别是7.8和13.6（P〈0.05）.定量PCR研究表明,血红素加氧酶-1和吲哚胺2,3双加氧酶mRNA在胎盘高表达,在脾脏低表达（P〈0.05）.父系来源的移植皮片的平均存活时间在妊娠组和非妊娠组分别是7.67和7.08天,无统计学差异（P〉0.05）.由此认为,在小鼠妊娠过程中,尽管出现了具有免疫抑制功能的Treg的比例增加,尽管有针对父系来源刺激细胞的较低的MLR反应性,但是单次妊娠对于父系来源的移植皮片的存活,在本研究条件下,未能显示具有统计学意义的保护作用.     

大熊猫9个BAC的测序、注释和进化分析

本文构建了相当于大熊猫10倍基因组覆盖度的BAC文库, 并随机挑选了其中9个BAC进行测序和组装, 9个BAC的选择满足更多基因更少重复序列的原则. 这9个BAC的组装将为评估基于新一代Illumina GA测序技术的大熊猫全基因组测序及组装的准确性提供有效资源. 运用同源比对和从头预测的方法, 对9个BAC, 共约878 kb的序列进行了基因和重复序列的注释以及进化分析. 一共预测到12个蛋白编码基因, 其中, 7个基因匹配到同源基因的功能注释. 这7个基因平均大小约41 kb, 编码区平均大小约1.2 kb, 每个基因平均约含6个外显子. 同时预测到7个tRNA基因. 大约27%的序列被注释为重复序列. 同时, 基于邻接法, 构建了包含人、小鼠、狗、猫以及大熊猫5个物种的物种进化树, 结果显示狗的基因与其他4个物种相比距大熊猫最近. 本实验结果提供了大熊猫9个BAC的详细序列及注释信息, 为对大熊猫的研究提供了数据资源.